bug#62216: Odd file corruption in clojure mode and emacs 30 HEAD

[Jonathon McKitrick]

On Thu, Aug 31, 2023 at 06:54:23PM +0300, Eli Zaretskii wrote:
: > Date: Thu, 31 Aug 2023 14:46:01 +0000
: > From: Jonathon McKitrick <jcm@SDF.ORG>
: > Cc: Eli Zaretskii <eliz@gnu.org>, luangruo@yahoo.com, eggert@cs.ucla.edu,
: >         62216@debbugs.gnu.org
: > 
: > On Wed, Aug 30, 2023 at 02:07:35PM +0200, Gerd Mllmann wrote:
: > : On 30.08.23 14:00, Eli Zaretskii wrote:
: > : > > From: Gerd Möllmann <gerd.moellmann@gmail.com>
: > : > > Cc: Jonathon McKitrick <jcm@SDF.ORG>,  Eli Zaretskii <eliz@gnu.org>,  
Paul
: > : > >   Eggert <eggert@cs.ucla.edu>,  62216@debbugs.gnu.org
: > : > > Date: Wed, 30 Aug 2023 10:59:08 +0200
: > : > > 
: > : > > Po Lu <luangruo@yahoo.com> writes:
: > : > > 
: > : > > > Jonathon McKitrick <jcm@SDF.ORG> writes:
: > : > > > 
: > : > > > > What's the best mechanism to log these values in emacs?
: > : > > > 
: > : > > > In this case, printf.
: > : > > 
: > : > > When I add this assumption:
: > : > > 
: > : > > modified   src/fileio.c
: > : > > @@ -4805,8 +4805,11 @@ DEFUN ("insert-file-contents", 
Finsert_file_contents, Sinsert_file_contents,
: > : > >       /* 'try' is reserved in some compilers (Microsoft C).  */
: > : > >       ptrdiff_t trytry = min (gap_size, READ_BUF_SIZE);
: > : > > +     ptrdiff_t trytry_old = min (total - inserted, READ_BUF_SIZE);
: > : > >       if (!NILP (end))
: > : > >         trytry = min (trytry, total - inserted);
: > : > > +     if (trytry != trytry_old)
: > : > > +       abort ();
: > : > >       if (!seekable && NILP (end))
: > : > >         {
: > : > > 
: > : > > and make bootstrap, temacs aborts.
: > : > > 
: > : > > Can someone tell if this assumption should hold?
: > : > 
: > : > You expect READ_BUF_SIZE to never be greater than gap_size?
: > : 
: > : Don't know.  This is how I understood Jonathan's nail saying works with 
this
: > : old code, doesn't work with this new code.
: > 
: > I'm willing to log some meaningful stats if that would help. Last time I 
logged these values, I was inundated with info, but if I could
: > narrow it down to the most useful cases, I could log the relevant bits and 
report back.
: 
: you mean, the fix I installed on master yesterday didn't fix your
: problem?  It did fix Gerd's problem.

Ahhh! I didn't realize that's what that was, lol. I'll try a new build without 
my patch.

Jonathon McKitrick
--
'My other computer is your Windows box.'